1. Field
Embodiments relate to a liquid crystal display device and a method of manufacturing the same.
2. Description of the Related Art
Generally, a liquid crystal display panel is a light receiving type display device that forms an image with external light incident thereon.
Since a liquid crystal display panel cannot emit light by itself, a backlight unit may be installed behind the liquid crystal display panel and may irradiate light toward the panel. Therefore, an image may be viewed even in a dark location. A backlight unit may also be used as a surface light source device, e.g., an illuminated signboard.
A liquid crystal display panel may include liquid crystal between two substrates. When power is supplied, the liquid crystal display panel may display, e.g., images, numbers, and texts, by rearranging liquid crystal molecules. Liquid crystal display panels may be categorized into various types based on driving mechanisms, displaying mechanisms, and display arrangements. A thin-film transistor (TFT) type liquid crystal display panel may refer to a panel in which transistors are uniformly arranged in each pixel on a substrate.
Recently, in order to miniaturize a liquid crystal display panel, thicknesses of the substrates have been further reduced. However, if each function layer is formed on the substrates after the thicknesses of the substrates are reduced, the substrates with reduced thicknesses may be undesirably damaged or deformed. In addition, patterns of each of the function layers may become defective during fabrication of each of the function layers, e.g., by a baking process at a high temperature.
Therefore, thicknesses of the substrates may be reduced by forming each of the function layers on the substrates and then etching the substrates. However, if the substrates are etched by using a conventional etching solution, it may be difficult to control formation of defect holes in the substrates.
For example, depths of defect holes in a substrate may be about 10 micrometers to about 50 micrometers. It may be possible to reduce sizes of defect holes by polishing and removing about 5 to about 10 micrometers from an etched substrate.
However, there is a limit to reducing the polished thickness of an etched substrate when the etched substrate is polished by using a polisher. Therefore, defect holes may remain in the substrate.
Especially, in mass production, defect holes may be scattered throughout a plurality of substrates, and thus it is difficult to select substrates to be polished.
Furthermore, even if sizes of defect holes are reduced by polishing substrates, the probability that the polished substrate is determined to be good is below 70%. Furthermore, compared to the recent trend of reducing a thickness of a substrate, sizes of defect holes are increasing. Therefore, the probability of defects further increases.